They do become tradable upon getting to pink limited status, however the brokers systems are not caught up yet. Right now it looks like the updates or manual after OTC markets makes the change, so a lot of the pink limited and even some pink current stocks are still not tradable.
I spoke with a trading supervisor at Schwab about a month ago and she said that they are hoping to have this update made daily. That would obviously require an automated feed from OTC markets to Schwab. She was noncommittal on the time frame for this but said sometime in the fourth quarter. I would assume other brokers face the same issue. I can buy a slightly different set of stocks at IB than I can at Schwab. There are a few more stocks that are by eligible at IB then it Schwab. I have not found any yet that I can buy at Schwab that I cannot buy at IB.
Schwab changed things slightly a couple days ago. Some still say "closing transactions only", while others say "you must call a broker to buy this stock". I think this is further evidence that the systems have not caught up yet, and Schwab is being careful to spin the buying limitations on those a "systems issue" as opposed to a "policy issue".
I did have one stock (IPTK, you should take a look at it!) finally move back to buyable status yesterday after going to pink current way back in early August.
Personally, I think they could have found an intern to update their internal list once a week while waiting for the automated feed...
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